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| Mirrors > Home > NFE Home > Th. List > 19.23tOLD | Unicode version | ||
| Description: Obsolete proof of 19.23t 1800 as of 1-Jan-2018. (Contributed by NM, 7-Nov-2005.) (Proof modification is discouraged.) (New usage is discouraged.) | 
| Ref | Expression | 
|---|---|
| 19.23tOLD | 
 | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | exim 1575 | 
. . 3
 | |
| 2 | 19.9t 1779 | 
. . . 4
 | |
| 3 | 2 | imbi2d 307 | 
. . 3
 | 
| 4 | 1, 3 | syl5ib 210 | 
. 2
 | 
| 5 | nfnf1 1790 | 
. . 3
 | |
| 6 | nfe1 1732 | 
. . . . 5
 | |
| 7 | 6 | a1i 10 | 
. . . 4
 | 
| 8 | id 19 | 
. . . 4
 | |
| 9 | 7, 8 | nfimd 1808 | 
. . 3
 | 
| 10 | 19.8a 1756 | 
. . . . 5
 | |
| 11 | 10 | a1i 10 | 
. . . 4
 | 
| 12 | 11 | imim1d 69 | 
. . 3
 | 
| 13 | 5, 9, 12 | alrimdd 1768 | 
. 2
 | 
| 14 | 4, 13 | impbid 183 | 
1
 | 
| Colors of variables: wff setvar class | 
| Syntax hints:     | 
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1546 ax-5 1557 ax-17 1616 ax-9 1654 ax-8 1675 ax-6 1729 ax-11 1746 | 
| This theorem depends on definitions: df-bi 177 df-ex 1542 df-nf 1545 | 
| This theorem is referenced by: (None) | 
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